SOLUTION: A swimmer aims his body North directly across a 80 m river at a velocity of 1.2 m/s. If the river is moving West at 0.7 m/s, (a) how far downstream will he land and (b) how long wi
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-> SOLUTION: A swimmer aims his body North directly across a 80 m river at a velocity of 1.2 m/s. If the river is moving West at 0.7 m/s, (a) how far downstream will he land and (b) how long wi
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Question 1173878: A swimmer aims his body North directly across a 80 m river at a velocity of 1.2 m/s. If the river is moving West at 0.7 m/s, (a) how far downstream will he land and (b) how long will it take him to cross the river? Found 2 solutions by Alan3354, ikleyn:Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! A swimmer aims his body North directly across a 80 m river at a velocity of 1.2 m/s. If the river is moving West at 0.7 m/s, (a) how far downstream will he land and (b) how long will it take him to cross the river?
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Assuming "aims his body north" means he swims facing North:
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If the river is moving West at 0.7 m/s
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Currents and wind are given as the direction they're from.
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It's a vector problem with a right triangle.
His speed is the hypotenuse with sides of 1.2 and 0.7
c^2 = 1.2^2 + 0.7^2
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Time to cross = 80/c = t
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Distance downstream = 0.7*t